Factbox: A look at past U.S. government shutdowns

(Reuters) - A U.S. government shutdown began at midnight on Thursday after Congress failed to pass a stopgap funding measure needed to extend current funding authority for most federal agencies.

The Senate approved the stopgap measure early on Friday morning, along with a two-year deal on spending limits. But the package still needed approval from the House of Representatives before it could be signed into law by President Donald Trump.

The shutdown is the second in 2018. The government shut down for three days in January, when Congress reached an impasse over government spending levels and immigration legislation. But, since it was largely over a weekend, many government agencies and services were not affected.

Past government shutdowns have done little lasting economic damage but these events can hurt federal workers, rattle markets and shake confidence in the United States abroad.

Since Congress implemented the modern budget process in the mid-1970s, there have been 19 gaps in government funding, according to the Congressional Research Service (CRS), but not all resulted in true government shutdowns.

FILE PHOTO - U.S. Capitol is seen shortly after beginning of the Government shutdown in Washington, U.S., January 20, 2018. REUTERS/Yuri Gripas

Here are the three occasions when funding lapsed and significant government shutdowns occurred.

November 1995: Government funding elapsed for five full days from Nov. 14 to 19 and about 800,000 workers were furloughed after Democratic President Bill Clinton vetoed spending legislation passed by the Republican-controlled Congress, according to a CRS report.

December 1995 and January 1996: Clinton’s continued clash with congressional Republicans over funding levels for the Medicare health insurance program for the elderly, education and other issues resulted in a second lapse in government funding for 21 full days from Dec. 16, 1995 to Jan. 6, 1996, when about 280,000 workers were furloughed, according to the CRS.

October 2013: During this standoff, government funding elapsed for 16 full days from Oct. 1 to 17 and about 800,000 federal workers were furloughed, according to the CRS. More than 1 million more reported to work without knowing when they would be paid, according to media reports.

The shutdown occurred after conservative Republicans in the House of Representatives attempted to use the budget process to delay or defund implementation of Democratic President Barack Obama’s Affordable Care Act, known as Obamacare.

The impasse between the House and the Democratic-controlled Senate, along with Obama, ended after both chambers passed a Senate-brokered bill with stricter income verification requirements on people obtaining health insurance through Obamacare. The deal to end the shutdown coincided with a deadline to raise the U.S. debt ceiling, the country’s borrowing limit.